In the foodservice area, post-mix beverage dispensers are known which mix a concentrate or syrup with several measures of water and then dispense the mixture on demand to reconstitute a hot or cold beverage such as juice, carbonated sodas, coffee or tea. Coffee, tea or soda concentrates are relatively easy and safe to store in bags at ambient temperature as they usually contain a high amount of solids and/or sugar, a low pH and a low water activity, and these make them relatively stable over time. These concentrates can hardly become contaminated and the risk of food poisoning is very low.
More serious sanitary problems may occur with more microbiologically sensitive products, such as low acid fluids that can enter into the composition of an on-demand prepared beverage or food. For instance, milk is naturally a low acid fluid comprising a relatively balanced proportion of proteins, lipids and glucids with a pH of about 6.7. This formulation provides a favorable ground for critical bacterial growth. Milk can be rapidly spoiled when it becomes in contact with contaminated moisture, dust, fluid, etc., and thus proper handling and dispensing of such a product is tricky.
Therefore, in order to ensure a longer shelf life and prevent hygienic hazards, it is common to equip the dispensing system with a dry zone wherein the milk is provided under the form of powder, because that form is less sensitive to microbial growth. For example, U.S. Pat. No. 4,211,342 relates to a dispenser able to deliver hot and cold drinks that is relatively complex and uneasy to manage since both syrup and powder must be handled in order to reconstitute beverages.
Another solution for increasing the shelf life of a low acid fluid and reducing hazards due to bacterial growth in automated dispensers consists in maintaining refrigeration in the dispensing unit with a temperature range which is less favorable to rapid microbial growth, i.e., at or under 6-8° C. For example, U.S. Pat. No. 5,797,519 relates to a post-mix beverage dispenser for tea, coffee and the like in which refrigeration is maintained by a cooling unit. However, cooling does not eliminate the daily cleaning and sanitization requirements for the dispenser. Furthermore, refrigeration only slows down the growth process but does not reduce all bacterial and hygienic problems. It also adds to the overall and maintenance costs of the machine and is energy consuming.
Therefore, there is a need for handling microbiologically sensitive fluids, such as milk-based components, that are used to form the composition of beverages or food preparations, more preferably without refrigeration, in a more effective and convenient way while reducing the risk of bacterial contamination and growth while constantly maintaining a high degree of food safety.
U.S. Pat. No. 6,240,952 relates to an aseptic product dispensing system which comprises a sanitary connection assembly interposed in fluid communication with a substantially aseptic product source and a substantially conventional product dispenser. The sanitary connection assembly is provided with an automated cleaning system whereby combination of pressurized gas, flushing fluid and/or sanitizing solution may be injected into, and thereafter evacuated from, the sanitary connection assembly. Product loading is carried out by automated engagement of a hose connector to a cavernous body that results in puncturing of a perforable cover that closes the hose connector. The connector is protected by a check valve for preventing backflow into the product after the membrane is broken. The connection of the bag to the sanitary connection is relatively complex and expensive, but without providing the desired improvements in cleaning efficiency and safety. More particularly, the hose connector is likely to cause important bacterial contamination and growth problems, in particular in the zone between the check valve and the pinched point located further upstream the hose portion. It is known that check valves are never perfectly air tight because of the possible rotation of the ball. If this critical portion becomes contaminated, the micro-organisms can rapidly grow and spoil the entry of the sanitary connection without any possibility to cure this hygienic issue except for replacement of the valve. Furthermore, the sanitary connection system is relatively complex by itself as it also requires two cavities selectively controlled by a valve to enable the flushing of inside entry of the connector independently from the dispensing line.
Accordingly, there is a need for an improved sanitary system that is not subject to these problems and disadvantages and can handle a microbiologically sensitive fluid, such as a shelf stable low acid concentrate, in a more reliable, effective, convenient, simpler and less costly way.